1. Field of the Invention
The present invention relates to an ink jet recording head which has pressure producing chambers adapted to be pressurized by a pressure generator to jet ink droplets from nozzles.
2. Description of the Related Art
An ink jet recording head has a plate provided with a plurality of independent nozzles arranged in a row and a plurality of pressure producing chambers arranged in a row and connected to a common ink chamber. The ink jet recording head jets ink droplets from the nozzles by changing the volumes of the pressure producing chambers by piezoelectric vibrators or by vaporizing ink with heating devices.
The pressure producing chambers of the ink jet recording head must be arranged regularly at pitches corresponding to recording density. Therefore, the pressure producing chambers are formed by etching a plate or by an injection molding process using a polymeric material.
When it is desired to form the pressure chambers accurately in the plate by etching, an expensive silicon single crystal must unavoidably be used as the plate and the pressure producing chambers must be formed by anisotropic etching.
Although a plate of a polymeric material provided with pressure producing chamber can relatively easily be formed high accurately by an injection molding process, the plate is liable to be broken due to fatigue caused by repeated cyclic stress induced by piezoelectric vibrators or liable to be deteriorated by repeated heating by the heating devices.